1. Field of the Invention
This invention relates to an electronic data management system and method, and more particularly relates to an electronic data management system and method capable of determining the authenticity of electronic data.
2. Description of Background Art
When a customer places an order with a manufacturer, products different from a drawing submitted with the order may be delivered. Particularly, when electronic (numerical) data is submitted as the drawings for the ordered products, the following reasons can cause deficient products.
1. A manufacturer has made a mistake in the process of manufacturing the products.
2. A manufacturer has altered the drawings and then manufactured the products according to the altered drawings.
3. A customer has altered the drawings after placing the order.
Whether or not an electronic drawing is altered can be determined by installing an authentication system into both the customer's and manufacturer's computer systems.
An authentication system, for example, as disclosed in Japanese Patent Publication Laid-open No. Hei. 9-198437, is designed to be capable of determining whether or not the electronic document is altered according to authentication information recorded within the electronic document (i.e. electronic drawing) and authentication information recorded in the computers of both the customer and the manufacturer.
However, with the authentication system described above, each time an authentication is executed at each computer system, the authentication information is required to be recorded in a computer and within an electronic document, and the authentication process therefore becomes complicated.
And as this authentication system requires the installation of management functions to record the authentication information in each computer, the configuration of the computer system becomes complicated.
Moreover, this authentication system has difficulty in determining which customer or manufacturer has altered an electronic document in cases where an electronic document is altered after authentication. Therefore, it has been difficult to specify the reasons 1 though 3 above in order to clarify exactly where the responsibility lies for a deficient product.